The present disclosure relates to subject matter contained in Japanese Patent Application No. 10-22474 (filed on Feb. 4, 1998), which is expressly incorporated herein by reference in its entirety.
1. Field of the Invention
The present invention relates to a treating instrument used through an instrument-inserting channel of an endoscope.
2. Description of the Prior Art
A treating instrument for an endoscopic treatment, such as a biopsy forceps used with an endoscope, has a pair of treating members provided at the distal end of a sheath that is removably inserted into an instrument-inserting channel of an endoscope. The pair of treating members are opened or closed in a beaklike manner by remote control conducted at the proximal end of the sheath.
Such endoscopic treating instruments include two different types: a bilaterally opening type in which both a pair of treating members are opened or closed in opposite directions through the same angle; and a unilaterally opening type in which only one of a pair of treating members is rotatable to perform an opening and closing action, the other being fixed.
The unilaterally opening type is clumsy and likely to cause a misoperation because only one treating member is rotatable when the treating instrument is used to hold the mucous membrane of an affected part between the pair of treating members. For this reason, the bilaterally opening type is widely used.
If an affected part on the mucous membrane surface in a body cavity lies just in front of a treating instrument projecting from the instrument-inserting channel of an endoscope, the above-described conventional bilaterally opening type of treating instrument can be effectively used. In such a case, the mucous membrane of the affected part can be readily held with the pair of treating members to perform a necessary endoscopic treatment.
However, when an affected part to be treated is situated where the pair of treating members of the endoscopic treating instrument can be aimed at it only in a diagonal direction (such cases are encountered quite often in actual practice), it is difficult to hold the mucous membrane of the affected part with the pair of treating members. Therefore, there are not a few cases where an endoscopic treatment cannot smoothly be performed.